Hundreds of flights across the US are delayed after a major IT outage hit at least 5 airlines

Hundreds of flights were delayed on Monday morning after several major airlines experienced an IT issue with a service called AeroData.

The affected airlines include American Airlines, Southwest Airlines, Delta Air Lines, United Airlines, JetBlue, and Alaska Airlines.

More than 500 flights were behind schedule at airports in Chicago, New York, Texas, Boston, Atlanta, Miami, and Detroit.

Passengers started reporting on delays linked to a nationwide IT problem at about 3.30 a.m. Five hours later, the Federal Aviation Administration said the issu was resolved.

Flights at airports across the US were delayed early Monday because of an IT failure affecting at least five airlines, the US Federal Aviation Administration (FAA) said.

Southwest Airlines, Delta Air Lines, United Airlines, JetBlue, and Alaska Air were hit, causing widespread delays, the authority told Business Insider.

“Several airlines are experiencing issues with a non-FAA flight planning weight and balance program called AeroData. Mainline operations and regional operations are affected to varying degrees,” a spokeswoman said.

The FAA tweeted the issue was resolved at 8:34 a.m. ET on Monday, around five hours after passengers first began posting to social media describing IT problems affecting their flights.

While the problem was still going on, airlines responded to passengers on Twitter, blaming a computer administration issue:

I completely apologize, we are currently experiencing a System-Wide Outage we are working diligently to get it back up and running. We do not have a specific time as yet. TMC

United Airlines told Business Insider that around 150 of its flights were hit. A spokeswoman said: “Some of our regional carriers experienced an issue with a flight planning program this morning that impacted operations, resulting in delays for select United Express flights.”